Authentic
graded by Al-Albani
Mishkat al-Masabih 4525
وَعَنْ عَائِشَةَ وَرَافِعِ بْنِ خَدِيجٍ عَنِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «الْحمى من فيج جَهَنَّم فَأَبْرِدُوهَا بِالْمَاءِ»
‘A’isha and Raf’i b. Khadij reported the Prophet as saying:
“Fever is due to the vehemence of the heat of hell, so cool it with water.” (Bukhari and Muslim.).
Cited in Mishkat al-Masabih (No. 4525).